The embodiment relates to an inverter. In particular, the embodiment relates to a method of detecting a non-connection state of a high-voltage cable constituting an inverter.
An inverter system serving as a motor controller employed in an eco-friendly vehicle is an electric/electronic substrate assembly (ESA) to convert high-voltage DC power into AC power or DC power for the purpose of controlling a motor. The inverter system is a main component constituting an electric motor of a vehicle.
The above-described eco-friendly vehicle employs a permanent magnet motor as a driving unit. The motor applied to the eco-friendly vehicle while serving as the driving unit is driven by phase current transferred from the inverter, which converts DC voltage into 3-phase voltage, through the first high-voltage power cable according to a pulse width modulation (PWM) signal of a controller.
In addition, the inverter converts DC-link voltage, which is transferred through the second high-voltage power cable according to the switching operation of a main relay, into 3-phase voltage.
Accordingly, if one of the first power cable, which connects the inverter with the motor, or the second power cable, which connects the high-voltage battery with the inverter, is disconnected, the motor is not smoothly driven. In addition, high voltage/high current is induced to a system, so that the whole inverter system is broken down, which may cause a fatal problem.
FIG. 1 is a view showing a device of detecting the disconnection state of a power cable in an inverter system according to the related art.
Referring to FIG. 1, a device of detecting the disconnection state of the power cable according to the related art includes a power cable 10 and a disconnection detecting unit 20 connected with the power cable 10 to transmit a signal based on the disconnection state of the power cable 10 to the controller.
The disconnection detecting unit 20 is connected to the power cable 10 to transmit a digital signal based on the connection state of the power cable 10 to the controller.
In other words, according to the related art, a disconnection detecting unit for checking the disconnection state of the power cable 10 is installed on the power cable 10 in the form of a hardware separately provided from the power able 10, and the disconnection state of the power cable 10 is checked in real time by using a digital signal output from the disconnection detecting unit.
However, since the disconnection detecting unit for the power cable 10 detects the disconnection state of the power cable 10 in the form of a hardware, the above disconnection detection unit has limitations in terms of space as well as a price.
In addition, the above disconnection detecting unit of the power cable 10 may be erroneously operated due to external causes.